rmsdata.java

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package x;

import javax.microedition.rms.*;
import java.io.*;
import java.util.*;

public class RMSData
{
	public static String title,parent,table,child,adress;
	public RMSData()
	{
		
		
		
	}
	
	public static byte[] encode(String title,String parent,String table,String child,String adress)
	{
		byte[] result=null;
		try
		{
			ByteArrayOutputStream bos=new ByteArrayOutputStream();
			DataOutputStream dos=new DataOutputStream(bos);
			dos.writeUTF(title);
			dos.writeUTF(parent);
			dos.writeUTF(table);
			dos.writeUTF(child);
			dos.writeUTF(adress);
			result=bos.toByteArray();
			dos.close();
			bos.close();
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return result;
	}
	
	public static void decode(byte[] data)
	{
		try
		{
			ByteArrayInputStream bis=new ByteArrayInputStream(data);
			DataInputStream dis=new DataInputStream(bis);
			title=dis.readUTF();
			parent=dis.readUTF();
			table=dis.readUTF();
			child=dis.readUTF();
			adress=dis.readUTF();
			dis.close();
			bis.close();
		}	
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
	
	public static RecordStore openRsAnyway(String table)
	{
		RecordStore rs=null;
		if(table.length()>32)
			return null;
		try
		{
			rs=RecordStore.openRecordStore(table,true);
			return rs;
		}
		catch(Exception e)
		{
			e.printStackTrace();
			return null;
		}
	}
	
	public static boolean writeRS(String tableName,String title,String parent,String table,String child,String adress)
	{
		RecordStore rs=openRsAnyway(tableName);
		if(rs==null)
		{
			System.out.println("table open fail");
		}
		else
		{
			try
			{
				byte tmp[]=encode(title,parent,table,child,adress);
				rs.addRecord(tmp,0,tmp.length);
				rs.closeRecordStore();
			}
			catch(Exception e)
			{
				e.printStackTrace();
				return false;
			}
		}
		return true;
	}
	
	public static Vector readRS(String tableName)
	{
		RecordStore rs=openRsAnyway(tableName);
		Vector vector=new Vector();
		
		if(rs==null)
		{
			System.out.println("table open fail");
		}
		else
		{
			try
			{
				RecordEnumeration re=rs.enumerateRecords(null,null,false);
				while(re.hasNextElement())
				{
					
					byte tmp[]=re.nextRecord();
					decode(tmp);
					menuStruct menuStruct=new menuStruct(title,parent,table,child,adress);
					vector.addElement(menuStruct);
				    
				}
				rs.closeRecordStore();
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
		}
//		System.out.println("menu.vector"+vector.size());
		return vector;
	}
	
	public static boolean deleteRS(String tableName)
	{
		RecordStore rs=openRsAnyway(tableName);
		if(rs==null)
		{
			System.out.println("table open fail");
		}
		else
		{
			try
			{
				RecordEnumeration re=rs.enumerateRecords(null,null,false);
				while(re.hasNextElement())
				{
					int id=re.nextRecordId();
					rs.deleteRecord(id);
				}
				rs.closeRecordStore();
			}
			catch(Exception e)
			{
				e.printStackTrace();
				return false;
			}
		}
		return true;
	}
	
	public static boolean updateVersion(String tableName,String value)
	{
		RecordStore rs=openRsAnyway(tableName);
		if(rs==null)
		{
			System.out.println("table open fail");
		}
		else
		{
			try
			{
				RecordEnumeration re=rs.enumerateRecords(null,null,false);
				while(re.hasNextElement())
				{
					int id=re.nextRecordId();
					title=value;
					
					
					byte tmp[]=encode(title,"xx","xx","xx","xx");
					
					rs.setRecord(id,tmp,0,tmp.length);
					break;
				}
				//rs.setRecord(0,tmp,0,tmp.length);
				rs.closeRecordStore();
			}
			catch(Exception e)
			{
				e.printStackTrace();
				return false;
			}
		}
		return true;
	}
	public static boolean downloadFlag(String tableName,String value)
	{    System.out.println("rmsFlag");
		RecordStore rs=openRsAnyway(tableName);
		boolean Flag=false;
		String version;
		
		if(rs==null)
		{
			System.out.println("table open fail");
		}
		else
		{
			
			try
			{
				if(rs.getNumRecords()==0)
				{
					//锟斤拷锟斤拷锟斤拷
					rs.closeRecordStore();
				
					updateVersion(tableName,value);
					
					Flag=true;
					
				}
				else
				{
					//锟斤拷锟斤拷
					Vector vector=new Vector();
					vector=readRS(tableName);
					menuStruct menuStruct=(menuStruct)vector.elementAt(0);
					version=menuStruct.getTitle();
					System.out.println(version+","+value);
					
					if(version.equals(value))
					{   System.out.println("version"+version+value);
						Flag= false;
					}
					else
					{
						updateVersion(tableName,value);
						System.out.println(version+","+value);
						Flag= true;
					}
				}
				
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
		}
		System.out.println(Flag);
		return Flag;
		
	}
}